Method of attaching articles



Feb. 8, 1944. M. MccANN METHOD OF ATTACHING ARTICLES Original Filed May 25, 1940 gmc/WIM mac/mL me can Patented Feb. 8, 1944 stares es 'i` ENCE'.

METHOD F ATTACHING ARTICLES Michael McCann, Ozone Park, N. Y., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New `l'ersey 6 Claims.

This application is a division of my United States patent application Serial No. 337,161, led May 25, 1946.

The present invention relates to a method of attaching articles to work and it has as a primary object to provide an improved method of attaching articles whereby the beginning end of the thread will be securely bound to the work by the succeeding stitches tov prevent ravelling and by means of which the visible portion of the beginning end will be reduced in length and therefore will be rendered comparatively` inconspicuous.

This improved method comprises, essentially, holding the beginning end portion of the thread beneath and adjacent to the underside of the work and thereafter forming Va plurality of article-attaching stitches through the article and work, such stitches embracing and covering a material part of the beginning end portion of the thread.

The present method is particularly well adapted for the attaching of flatbuttons to work and while it may be performedby hand, if desired, it

may be carried out more expeditiously by button,`

sewing machines of which one form is disclosed in my abovernentioned patent application.

For convenience,A this invention will be shown and described in connection with the attaching of fiat buttons by the machine disclosed in my above mentioned patent application but it is to be understood that it may also be practiced in connection with the attachment of other articles and by other machines, and, if desired, by hand as above sta-ted. In other words, the ,present dis-A closure is to be taken as illustrative but in no sense as limiting.

In the accompanying drawing constituting a part of this disclosure Fig. l is a front end View of a portion of'a sew-- ing machine which may be used to practice the present improved method of attaching articles.

Fig. 2 is a disassembled perspective View of the throat-plate and elements Aofthe thread-cutting and -nipping mechanism of the machine which is illustrated partially in Fig. l.

Figs. 3 and 4 are detail longitudinal sectional views of portions of the above mentioned sewing machinashowing more particularly the stitchforming mechanism and means for trimming 01T a portion of the beginning end of the thread and thereafter holding the thread in position to be embraced by the succeeding stitches,

Fig. 5 is a transverse sectional view'through the parts shown in Figs. 3 and 4, with the stitchforming elements in elevation.

Figs. 6, 7 and 8 are enlarged vertical sectional views through a work-piece and a button, illustrating the manner in which the nipped beginning end of the thread is drawn up and coveredv by the subsequent button attaching stitches.

Fig. 9 is a plan view of a portion of a work-piece and a four-hole fiat button attached thereto in accordance with the present improved method.

Referring more specically to the drawing, the machine illustrated for carrying out the present method includes a bracket-arm head l in which is mounted, for endwise reciprocation and lateral vibration, a needle-bar 2, carrying, at its lower end, an eyepointed needle 3 adapted to cooperate with a rotary chain-stitch loop-taker 1. Endwise reciprocation of the needle causes it to pass the thread through a hole in the button and the work therebeneath, while its lateral vibration shifts it from one to the other of a pair of holes. The specic means for actuating the needle-bar and loop-taker form no part of this invention and therefore detailed illustration and description thereof is deemed unnecessary. Sufce it to say that in its first reciprocation the needle carrying athread t passes downwardly through the button b (held by a. suitable button-clamp, not shown), through the work-piece w, through a needle-hole 5 formed in a .throat-plate and, in rising, presentsv a thread-loop to the looper l which engages that loop and pulls the end of' the thread below the throat-plate as indicated in Fig 3. Thereafter, at each reciprocation of the needle and each rotation ci the looper a chain stitch will be formed as is well understood by those skilled in the sewing machine art.

In its passage to the needle, the thread t passes through a stationary thread-eye l carried by the bracket-arm head (see Fig. I), thence downwardly and through a vertically movable thread-guide 8, thence upwardly and through a thread-guide 8 carried by the needle-bar 2, thence downwardly and through a light tension thread-guide it, through a thread-guide il carried by theA lower end of the needle-bar, and finally through the eye of the needle.

To prevent wasting of thread it is desirable that the length of the beginning end of the thread below the work be reduced to a minimum. Therefore, during the first upstroke of the neele, and while the thread-guide t is moving upwardly, the thread-guide is moved downwardly, thereby pulling out a bight of thread'between the thread-eye l and the thread-guide 5. The

thread, at that time, is clamped against movement through the thread-eye 1, by means not shown. This action causes a portion of the thread to be drawn back through the eye of the needle, leaving a relatively short length of thread beneath the work.

To the end that the finished work will have a neat appearance, it is essential that only a relatively short length of thread appear on the underside thereof and as it is impractical under certain operating conditions to draw the thread back so that precisely the same amount of thread end will appear beneath the work at each operation, it has been found desirable to initially provide a slight excess of thread-end and later to trim off that end at a predetermined distance from the work. This may be done by a threadcutting mechanism comprising an endwise reciprocable bar I2 having its forward end located beneath the throat-plate 6 and carrying a blade 3 provided with a cutting edge E4 which ccoperates with a stationary cutting edge I formed on a plate i3 secured to the underside of the throat-plate by screws Il. The major portion of the plate It is spaced from the throat-plate and the blade I3 operates between the two. The bar I2 and blade I3 are shifted back and forth at certain times by mechanism disclosed in my above mentioned patent application. The blade I3 is also used to move the end portion of the thread to a position in which it is transverse the path of lateral vibration of the needle and to hold it in that position so that the subsequent stitches will be formed over that portion of the thread as above mentioned, thereby to bind the thread to the work to prevent ravelling and to hide the major portion thereof.

The blade I3 also is formed with a thread-cutting edge I 3c which extends transversely of the vpath of rotation of the loop-taker and which, at

the completion of a sewing cycle, is shifted into the path of movement of the limb ZX of the thread-loop Z carried by the loop-taker, whereupon further movement of the loop-taker carries the limb of thread into contact with the cutting edge and severs the thread as indicated in dotted lines in Fig. 5.

When attaching four hole buttons as illustrated in Fig. 9, upon the completion of the sewing cycle through one pair of holes in a button, the button-clamp (not shown) and the button carried thereby are shifted by conventional means to position the other pair of holes in the button into the eld of action of the stitch forming mechanism whereupon the above described sewing cycle will be repeated in the second pair of holes in the button.

This positioning, trimming and nipping of the end portion of the thread and the final severing of the thread may be effected as follows: The blade I3 is so positioned relative to the needlehole in the throat-plate that, in its first downstroke, the needle passes through a notch I3a formed in one edge of the blade. After the needle has been retracted, the bar I2 and the plate I 3 carried thereby are shifted to the right, as seen in Fig. 3, to the position indicated in Fig. 4. This moves the end portion of the thread laterally, causes the cutting edges I4 and i5 to trim off the lower portion t thereof and nips the cut end of the thread between the underside of the throat-plate 6 and the upper side of a cross-bar I3b provided by the blade I3, all as shown in Fig. 4. i

When the present method is practiced by hand,

the beginning end of the thread may be held against the underside of the work by a thumb or finger of the sewer and the succeeding stitches formed to embrace and cover at least a portion of that thread-end to bind it to the work.

When the method is practiced by the machine disclosed in my above mentioned application, the thread-end is held to one side of the line of needle reciprocation as shown in Fig. 6, and a plurality of stitches are formed through a pair of holes in a button, the stitches embracing the oifset end portion t2 of the thread and being laid side-byside progressively toward the free end thereof, resulting in a product as shown in Fig. 8.

The progressive placing of the stitches sideby-side along the beginning end portion of the thread and toward the free end thereof is due to a plurality of conditions. Among these is the fact that the thread leads from the right side of the needle (as viewed in Figs. 6 and 7) and as the needle withdraws from the work and the needle puncture in the work closes due to expansion of the compressed fibers about the needle puncture the thread is urged toward the center of the needle puncture, or to the left as seen in Fig. 6. Also, in shedding each thread loop, the wing 'la of the looper forces the limb lx of the thread loop Z toward the left (Fig. '7) thereby constantly drawing to the left the group of stitches being formed so that each succeeding stitch is placed closer to the free end of the thread.

At the completion of the sewing cycle, the limb lX of the thread loop is severed close to the work as above described.

As shown by Fig. 8, in the finished product the thread-end t2 is firmly secured by each of the button-attaching stitches and the portion thereof which is visible on the under side of the work has been materially reduced in length thereby improving the appearance of the finished work.

Having thus set forth the nature of the invention what I claim herein is:

l. The method of attaching an article to work which comprises projecting a relatively long length of thread through the article and the work to the under side thereof, reducing the length of the thread projecting below the work holding a portion of said thread beneath and adjacent to the work and substantially parallel thereto, thereafter forming a plurality of stitches through said article and work, each of said. stitches, after the rst, being laid beside a preceding stitch and progressively toward the free end of and embracing that portion of the thread lying beneath the work, thereby binding the same to the work and reducing the length of thread Which is visible beneath the work.

2. The method of attaching an article to work which comprises projecting a relatively long length of thread through the article and through the Work, cutting off the end portion of the thread projecting below the work to reduce the length thereof nipping the thread beneath the work and adjacent thereto, and moving it laterally beneath the work to position a portion of the thread substantially parallel to one face of the work, repeatedly passing loops of the thread through the article and work alternately in different vertical planes on opposite sides of and progressively toward the free end of the portionV of thread beneath the work and concatenating said loops beneath the work to form a group of parallel attaching stitches embracing that portion of the thread beneath the work, and thereafter severing the last thread-loop beneath the work.

3. The method of attaching an article to Work by a plurality of disconnected groups of stitches which comprises projecting a thread through the article and through the Work, drawing a portion of the thread back through the work and article to reduce the length of the thread beneath the work, holding an end portion of the thread beneath and substantially parallel to the work, repeatedly passing loops of the thread through one portion of the article and work alternately in diierent vertical planes on opposite sides of said end portion of the thread and concatenating said loops beneath the work to form a first group of attaching stitches embracing said end portion of the thread, severing the last loop of thread beneath the work, and thereafter repeating the above described steps in a different portion of the article and work to produce a second group of attaching stitches spaced from the rst.

4. The method of attaching an article to work by a plurality of disconnected groups of stitches which comprises projecting a thread through the article and through the work, drawing a portion of the thread back through the work and article, cutting on" the end portion of the thread, nipping the thread beneath the Work and adjacent thereto, repeatedly passing loops of the thread through one portion of the article and work alternately at spaced points while holding the thread nipped, and concatenating said loops beneath the work to form a first group of attaching stitches. releasing said nipped thread, severing the last made thread-loop beneath the work` and thereafter repeating the above described steps in a different portion of the article and work to produce a second group of attaching stitches spaced from the rst.

5. The method of attaching an article to work bya plurality of disconnected groups of stitches which comprises projecting a loop of thread through the article and through the work, drawing a portion of the thread back through the work and article, holding an end portion of said thread beneath the work and adjacent thereto, repeatedly passing loops of the thread through one portion of the article and work alternately at spaced points while holding the end portion of the thread beneath t`he work, and securing said loops beneath the work to form a first group of attaching stitches, releasing said end portion of the thread, severing the last made threadloop beneath the work, and thereafter repeating the above described steps in a different portion of the article and work to produce a second group of attaching stitches spaced from the first.

6. The method of attaching an article to Work by a plurality of disconnected groups of stitches which comprises projecting a relatively long length of thread through the article and through the work, drawing a portion of the thread back through the work and article, cutting off the end portion of the thread below the work to reduce the length thereof holding the remaining thread beneath and substantially parallel to the work, repeatedly passing loops of the thread through one portion of the article and work alternately in diiTerent vertical planes on opposite sides of and progressively toward the free end of said end portion of the thread and securing said loops beneath the Work to form a rst group of attaching stitches embracing said end portion of the thread, severing the last loop of thread beneath the Work, and thereafter repeating the above described steps in a different portion of the article and work to produce a second group of attaching stitches spaced from the first.

MICHAEL MCCANN. 

